Mercurial > sdl-ios-xcode
view docs/html/sdlbuildaudiocvt.html @ 1260:80f8c94b5199
Date: 10 Jun 2003 15:30:59 -0400
From: Mike Shal
Subject: [SDL] Bug in SDL_wave.c?
Hey everyone, I'm not sure if this is a bug in SDL, or if I just have
incorrect WAV files. The problem I'm having is loading multiple
concatenated WAVs from SDL_LoadWAV_RW. Some WAV files put comments at
the end of the file (which may be bad form), and SDL doesn't skip past
them when reading from the RWops. So the next WAV I try to load will
start at the comment section of the previous WAV, which obviously
doesn't work. If anyone else is having this problem, one quick fix you
can do is run sox on the bad WAVs, which strips out all of the comment
sections.
Eg:
$ sox sound.wav tmp.wav
$ mv -f tmp.wav sound.wav
The other fix is to patch SDL_wave.c, which is included with this email.
(Assuming I made the patch correctly :). All it does is calculate how
much remaining space there is in the WAV file after the data chunk, and
does SDL_RWseek to skip it. I don't think it should interfere with
anything else, but if someone could check it that would be nice :). If
the bug is really with SDL and not with my WAVs, can someone work this
into the next version of SDL? Thanks,
-Mike Shal
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Tue, 24 Jan 2006 07:20:18 +0000 |
parents | 355632dca928 |
children |
line wrap: on
line source
<HTML ><HEAD ><TITLE >SDL_BuildAudioCVT</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ "><LINK REL="HOME" TITLE="SDL Library Documentation" HREF="index.html"><LINK REL="UP" TITLE="Audio" HREF="audio.html"><LINK REL="PREVIOUS" TITLE="SDL_AudioCVT" HREF="sdlaudiocvt.html"><LINK REL="NEXT" TITLE="SDL_ConvertAudio" HREF="sdlconvertaudio.html"></HEAD ><BODY CLASS="REFENTRY" BGCOLOR="#FFF8DC" TEXT="#000000" LINK="#0000ee" VLINK="#551a8b" ALINK="#ff0000" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >SDL Library Documentation</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="sdlaudiocvt.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdlconvertaudio.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SDLBUILDAUDIOCVT" ></A >SDL_BuildAudioCVT</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN7002" ></A ><H2 >Name</H2 >SDL_BuildAudioCVT -- Initializes a SDL_AudioCVT structure for conversion</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN7005" ></A ><H2 >Synopsis</H2 ><DIV CLASS="FUNCSYNOPSIS" ><A NAME="AEN7006" ></A ><P ></P ><PRE CLASS="FUNCSYNOPSISINFO" >#include "SDL.h"</PRE ><P ><CODE ><CODE CLASS="FUNCDEF" >int <B CLASS="FSFUNC" >SDL_BuildAudioCVT</B ></CODE >(SDL_AudioCVT *cvt, Uint16 src_format, Uint8 src_channels, int src_rate, Uint16 dst_format, Uint8 dst_channels, int dst_rate);</CODE ></P ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN7012" ></A ><H2 >Description</H2 ><P >Before an <A HREF="sdlaudiocvt.html" ><SPAN CLASS="STRUCTNAME" >SDL_AudioCVT</SPAN ></A > structure can be used to convert audio data it must be initialized with source and destination information. </P ><P ><TT CLASS="PARAMETER" ><I >src_format</I ></TT > and <TT CLASS="PARAMETER" ><I >dst_format</I ></TT > are the source and destination format of the conversion. (For information on audio formats see <A HREF="sdlaudiospec.html" ><SPAN CLASS="STRUCTNAME" > SDL_AudioSpec</SPAN ></A >). <TT CLASS="PARAMETER" ><I >src_channels</I ></TT > and <TT CLASS="PARAMETER" ><I >dst_channels</I ></TT > are the number of channels in the source and destination formats. Finally, <TT CLASS="PARAMETER" ><I >src_rate</I ></TT > and <TT CLASS="PARAMETER" ><I >dst_rate</I ></TT > are the frequency or samples-per-second of the source and destination formats. Once again, see <A HREF="sdlaudiospec.html" ><SPAN CLASS="STRUCTNAME" >SDL_AudioSpec</SPAN ></A >.</P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN7028" ></A ><H2 >Return Values</H2 ><P >Returns <SPAN CLASS="RETURNVALUE" >-1</SPAN > if the filter could not be built or 1 if it could.</P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN7032" ></A ><H2 >Examples</H2 ><P >See <A HREF="sdlconvertaudio.html" ><TT CLASS="FUNCTION" >SDL_ConvertAudio</TT ></A >.</P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN7037" ></A ><H2 >See Also</H2 ><P ><A HREF="sdlconvertaudio.html" ><TT CLASS="FUNCTION" >SDL_ConvertAudio</TT ></A >, <A HREF="sdlaudiocvt.html" ><TT CLASS="FUNCTION" >SDL_AudioCVT</TT ></A ></P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="sdlaudiocvt.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="sdlconvertaudio.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_AudioCVT</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="audio.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL_ConvertAudio</TD ></TR ></TABLE ></DIV ></BODY ></HTML >